Since the invention of the twisted nematic (TN) field-effect in 1970, the nematic liquid crystal display technology which is based on electric field-effects has made remarkable progress. Field-effects are characterized by polarization sensitive macroscopic molecular liquid crystal configurations with electrically tunable optical appearance. The unique electro-optical building block concept of field-effect LCDs enables the integration and individual optimization of anisotropic optical thin-films and silicon electronics in LCDs. The remarkable progress made over the past 45 years, renders today virtually all applications of the communication between man and machine possible. They range from reflective LCDs with “zero power” consumption, such as digital watch LCDs, or remotely controlled electronic price tags in Shopping centers, to iPhones and large size, ultra-high resolution 4k television LCDs. Since the beginnings in 1970 this development has been spurred by interdisciplinary R&D between physics, material sciences, synthetic chemistry, semiconductor electronics, and engineering. It includes TN-LCDs (1970), super-twisted nematic (STN)-LCDs (1980s), thin-film transistor (TFT)-addressed TN-LCDs for computer monitors in the early 1990s and beyond, and multi-domain LCD configurations. The latter became possible in the late 1990s either by electric fringe-field electrode geometries, or by photo-alignment/patterning of LC molecules. Further enhanced contrast, large angles of view and shorter response times were the result. Moreover, spin-offs into potential future types of field-effect LCDs, such as polymer stabilized blue phase LCDs and ferroelectric LCDs became possible. This development is reviewed with examples of the multidisciplinary R&D of the author and collaborators on electro-optical field-effects, liquid crystal materials and polarized optical alignment and alignment patterning of monomeric and polymeric liquid crystal molecules in LCDs and optical thin-films based on liquid crystal polymers.
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